Regular installation of sink and toilet plumbing in bathrooms

The water that enters the water is coming out, “say the plumbers when asked for an explanation of the basic methods of plumbing. Actually, it’s not that simple. If you are planning to install a bathroom toilet, you need a basic knowledge of plumbing or common techniques could end up with low water pressure, slow draining sink and a toilet gurgles and belches that. In addition to planning your water supply, you should consider venting drainage systems, both in the sink and in the toilet. In many communities, a plumber who is licensed to install all the system.

Water supply

If possible, you locate the sink and toilet along the same wall will reduce plumbing problems, since you only need to install pipes inside a single wall. This also applies when installing a bathtub or shower, but put the three fixtures on the same wall is not always feasible.

If you live in cold weather, avoid installing the water supply pipes on an exterior wall to reduce the risk of freezing.

Water compression distribution units use PEX tubing for individual water supply in each apparatus. The standard size of the tubing is 1/2 inch for the toilet and 3/8 inch for the sink. Red and blue tubes identify hot and cold water.

Drainage system

The drainage system operates by gravity. Individual sink and toilet drains are attached to a larger main drain flowing downward until it leaves the house through the main sewer drain.

Always consult local regulations before installing any type of plumbing. The standard slope for main drains is 1/8 to 1/4 inch (0.32 to 0.64 cm) per foot (30.5 cm) in length. That means the main drain pipe must have a steady downward slope. With less slope the solid waste from the toilet cannot flow efficiently. With too much slope the liquid content of the toilet can flow faster than the solid waste, leaving them in the drainage pipe.

Plumbing for the sink

The sink requires hot and cold water and a drain. The water supply pipe is connected to the bottom of the faucets and the drain with a U-shaped siphon is installed under the sink, which always has a little water to prevent the return of gases from the sewer to through the drain.


The water supply pipe is connected to the toilet tank to feed water into the tank after each use. Unlike the sink, the toilet contains its own drainage trap, so there is no need to install another. A 3 or 4 inch (7.6 or 10.2 cm) drain is installed under the toilet and a wax ring between the toilet and the drain to prevent leakage.


There should be a vent for the sink and toilet. Where the sink drain enters the wall, a hydraulic Tee is installed that directs the water drain downward, while venting the drain upward. The drainage configuration depends on the location of the sink in relation to the toilet and the rest of the accessories.

The toilet drain must also have a hydraulic vent tee. The two vent pipes are joined together in a main vent pipe throughout the house. This main vent pipe is directed up a wall and finally comes out through the roof.

Local regulations

The plumbing is subject to local regulations. Not only must the correct slope be observed in all drainage pipes; there may also be minimum distance requirements between the sink, toilet and other accessories. Most communities require obtaining a permit before installing any type of plumbing at home. Consult a professional plumber before installing any pipe.